Leveling Scissor Jacks

[SCADAMAN29325]

Thinking about installing 4 of these to level my 13k# class c. I've read NOT to use stabilizer Jack's to level, but these are listed as Leveling Scissor Jacks and are rated at 10k# each. Should be strong enough. Also mounting them at a 45deg angle.

Comments please.

Leveling Scissor Jack Set - 24" Lift - 10,000 lbs - QTY 2


Thanks, Phil

[valhalla360]

One thing to consider is the leveling systems I'm familiar with run 2 jacks at the same time (both front, both side or both rear). This causes the whole rig to rotate with the frame not twisting.

If you are doing it manually, one jack at a time, that can introduce a lot of twisting in the frame. Not a big deal for the frame as it's unlikely to fail but the house is bolted to the frame and not very strong...you might be opening up the seams in the roof as it all twists or loosening the screws holding the cabinets.

[ScottG]

Chris, the co's that make them always include a CYA statement that says they're only for stabilizing and not lifting. That being said, from my 40 yrs experience there's nothing wrong with using them up to their rating and maybe even a little beyond. After all, they are first and foremost "Jacks".
I can tell you that when they are very substantially overloaded, nothing dramatic happens. It simply bends the "jack" screw and thereafter causes the jack to wobble when extending or retracting.
I learned this when I forced mine to lift the whole side of my RV so I could change out a tire in some sand on the side of the road (thank you Carlisle).
Since then I'm sure I've overloaded them many times when leveling my rig and I was close but just needed a few extra turns. When I see the screw start to deflect, I stop (or at least soon after..).

[SJ-Chris]

Something I haven't been able to figure out... Is there something inherently bad about scissor jacks that make them not good for lifting an RV for leveling it?

Disclaimer: If I am ever going underneath my RV I always have multiple jacks and jack stands just in case for safety, and I suggest you do so also. This discussion is only as it pertains to leveling/lifting an RV with scissor jacks when at a campsite.

Many many many people will be quick to say, "scissor jacks are for stabilizing and not for jacking up your RV", but can you explain WHY?? People read that on the internet somewhere and then they are quick to regurgitate it without a real reason why.

Think about it for a minute....MOST regular cars (not RVs) come with a scissor jack for what?? For jacking up your regular car to replace a flat tire if needed. The scissor jack lifts up your regular car. Lifting is what a scissor jack is designed to do.

I would argue that your RV doesn't know WHAT KIND of jack you are using....scissor jack, bottle jack, floor jack, etc. Seems like the two main considerations would be 1)What weight limit is the jack rated at, and 2)Where are you jacking it up? For example, I routinely use a 12-ton bottle jack on my axle to jack up one rear side of my 30' Class C RV if I need to remove a tire. I'm pretty sure the RV would not care one bit if I used a properly weight rated scissor jack and lifted it from the same exact spot. Right? (Side note: This assumes you have proper contact and things don't slip while jacked up. Using the flat top of a scissor jack probably wouldn't be a good idea on a round axle jack location, but if the scissor jack were used on the flat portion of the frame AND bolted to the frame slipping would not be a worry.) My point is that a scissor jack that is rated to lift 9000lbs can lift the weight of half of the rear of my RV which is ~4500lbs.

AS LONG AS you are using a scissor jack that is weight rated to lift a side of your RV, can anyone explain what is wrong with using a scissor jack?? For example, my rear axle weight is about 9000lbs (total). Let's assume it is evenly distributed so that means 4500lbs on each side. If I use a scissor jack on one side and that scissor jack is weight rated for 9000lbs (double the weight of one side of my RV) what is the problem?

I *DO* see a potential problem with using a jack (ANY type of jack) to level your RV by lifting it AT THE WRONG LOCATION, where maybe you could bend the frame for example. BUT that seems like it would have nothing to do with using a scissor jack per se as you would have the same problem if you used a bottle jack or floor jack in an improper jacking location. Right??

One last example to prove my point.... A Class C RV DOES have 4 100% proper jack locations that we know about. Let's assume those 4 locations are on the front and rear axles right near the respective tires. Would you agree that it would be okay and do no damage to use 4 properly weight rated bottle jacks (or jack stands), one on each of those jack points to level your RV at a camping site? (Note: I wouldn't actually do this, but I'm trying to prove a point.) If you agree that no damage would happen in this scenario, then how about if the jacks were replaced with floor jacks that were properly weight rated. Any issue? I think not. Well what if those jacks were replaced with properly weight rated scissor jacks. Any issue? I think not.

If this thinking is correct, then would it be right to say that using scissor jacks to level your RV is ok as long as you use scissor jacks that are weight rated properly (I like to use 2x the actual load it is lifting) AND you are using a proper jack location? If so, it gets back to my previous question above regarding Where on the frame is it okay to jack up the RV (from an "I don't want to bend the frame or do any damage because of improper jack location" perspective)?

Ah.....I just thought of one other issue, and maybe this is the reason people say not to use jacks to level your RV, but I don't think I've read it anywhere before... I will wait for a bit to post the issue as I am curious to hear feedback on the above.

-Chris

PS: Have you ever seen an RV being worked on at a repair shop with a jack stand underneath the 4 jack points by each tire? I have. Doesn't seem to bother them.

[Grit_dog]

He meant rotated 45deg, not 45 deg out of plumb….

[SJ-Chris]

klutchdust wrote:
" suppose you could define Stabilizing as taking SOME of the load off the tires/leaf springs such that movement inside the RV is reduced when someone is walking around or when the wind is blowing (aka: Makes things more stable inside). Whereas Leveling could involve taking ALL the load off the tires/leaf springs with the primary goal of making the RV LEVEL inside (and secondarily making it also more stable since the load will be off the tires/leaf springs). When Leveling in this manner, it is possible that some of the tires could be literally off the ground and the weight on that side/corner will be supported wholly by the leveling jack."

^^^^^^
To get the wheels off the ground with these jacks what do you use as a crank. My cordless impact,lifting my trailer, bottoms out before the wheels even think about lifting off the ground. The hand crank is basically used once there is no weight on the jacks.
I can't imagine one of these would lift a class c off the ground. Stabilize against side by side movement, yes. But if these are not on the frame of the coach you are asking for issues in my opinion.
Think about it. If someone was going to change a tire and put the jack on the corner of your coach to lift it, what would you think would happen.

While I haven't tried to actually lift any side of a Class C RV with a scissor jack, I would think my impact wrench would be able to do it. Has anyone tried?

-Chris

[klutchdust]

" suppose you could define Stabilizing as taking SOME of the load off the tires/leaf springs such that movement inside the RV is reduced when someone is walking around or when the wind is blowing (aka: Makes things more stable inside). Whereas Leveling could involve taking ALL the load off the tires/leaf springs with the primary goal of making the RV LEVEL inside (and secondarily making it also more stable since the load will be off the tires/leaf springs). When Leveling in this manner, it is possible that some of the tires could be literally off the ground and the weight on that side/corner will be supported wholly by the leveling jack."

^^^^^^
To get the wheels off the ground with these jacks what do you use as a crank. My cordless impact,lifting my trailer, bottoms out before the wheels even think about lifting off the ground. The hand crank is basically used once there is no weight on the jacks.
I can't imagine one of these would lift a class c off the ground. Stabilize against side by side movement, yes. But if these are not on the frame of the coach you are asking for issues in my opinion.
Think about it. If someone was going to change a tire and put the jack on the corner of your coach to lift it, what would you think would happen.

[SJ-Chris]

nickthehunter wrote:
I am not an expert on the matter, but putting a support pillar way out on each end of a beam without knowing just how much load that beam is capable of supporting is a bad idea. Stabilizing and leveling are two way different concepts when it comes to how strong a beam needs to be.

I suppose you could define Stabilizing as taking SOME of the load off the tires/leaf springs such that movement inside the RV is reduced when someone is walking around or when the wind is blowing (aka: Makes things more stable inside). Whereas Leveling could involve taking ALL the load off the tires/leaf springs with the primary goal of making the RV LEVEL inside (and secondarily making it also more stable since the load will be off the tires/leaf springs). When Leveling in this manner, it is possible that some of the tires could be literally off the ground and the weight on that side/corner will be supported wholly by the leveling jack.

The official jack point on the rear (in a Class C) is on the axle itself. I would need to look underneath my RV to see exactly how this load is applied/distributed to the frame beam, but I believe it is somewhat spread across via the leaf spring. If I were to install a scissor jack on the beam itself AS CLOSE TO THE AXEL AS POSSIBLE (probably within ~3') I wonder if this is okay. Thoughts? Have any of you done this?

My gut feeling is that I would NOT want to install a scissor jack for leveling (lifting) "way out on the end of the beam" as that is probably ~8' behind the axle and that seems like it would put maximum stress on the frame beam. But would a scissor jack ~3' from the rear axle be okay?

Doing some searching online....
https://www.youtube.com/watch?v=Hfg70RzvaIk
(jump to 7:43 for an installation image from the manufacturer of one particular RV as ONE data point...)

or this video at ~1:20 shows leveling jack installed about 3' behind the rear axle...
https://www.youtube.com/watch?v=93dNz8Ft-tM

Or this one at 5:50 and 7:20...shows rear jacks ~3' behind the axle.
https://www.youtube.com/watch?v=1U0Igk0ZSa0

Those above videos seem to be leveling systems installed by professionals. Based on those, it seems like installing rear jacks ~3' behind the rear axles is likely okay. Anyone have more to add?

Thanks!
Chris

[nickthehunter]

I am not an expert on the matter, but putting a support pillar way out on each end of a beam without knowing just how much load that beam is capable of supporting is a bad idea. Stabilizing and leveling are two way different concepts when it comes to how strong a beam needs to be.

[ScottG]

Mine are mounted at 45 degrees on my TT. The jacks have so much play in them that I doubt it really makes any difference in performance so unless it's easy to do , I wouldn't mount them that way.
FWIW, I would go with a heavier jack. Doing so will cause it to be more stable and oftentimes they have dual bearings (for both extend and retract) and work a lot smoother over their life. You can also crank on them harder before the jack screw distorts.

[SJ-Chris]

Side note: My idea when I was considering doing this in the past was to also add this to my RV...

https://www.amazon.com/dp/B08HYKQPBQ

With this, you could have your RV leveled in just a minute or two!

Suggestion: If you do this, I would suggest that anytime your RV is jacked up you place the impact wrench (or whatever you use) on your driver seat or by the gas pedal so that you never accidentally drive away with your jacks still down!

Good luck!
Chris

[SJ-Chris]

Not sure what you mean by "45 degrees". Jacks need to be holding weight vertically straight up and not at an angle.

Perhaps what you mean is that your idea is to mount them so the access up/down adjustment port is not pointing straight out towards your sides so that they are less visible(?). That is fine but probably not necessary. It might be harder to mount them to the frame if you try to angle them that way. But if you did, as long as they are securely attached to the frame it would be okay.

If the purpose is to use these to level a few inches here and there while at a campsite, it should be fine (Pending input from others about my question above regarding mount location and potentially bending your frame). But you will want to make sure the weight carrying capacity of whatever jacks you use has plenty of margin and you shouldn't go underneath your RV with just these jacks holding it up.

-Chris

[SJ-Chris]

Note: Those jacks are rated at 5000lbs each, not 10,000lbs each.

Your rear axle is likely close to 9000lbs. So with 2 of those jacks in the rear (5000 + 5000 = 10000) you will be technically ok, but for me I would want more safety buffer/margin. For example, here is a 9000lb jack that actually costs less than the ones you mentioned:

https://www.amazon.com/LIBRA-Trailer-Stabilizer-Leveling-Scissor/dp/B08LTW81BS

With 2 of these in the heavy rear you will have lots of buffer (extra strength/margin).

Safety note: I would never climb underneath a lifted RV with just a scissor jack holding it up. Anytime I go under my lifted RV it has a bottle jack and multiple jack stands as backup.

I like the idea of what you are doing and considered doing it myself on my Class C RVs. It seemed like there was some easy spots in the rear to mount scissor jacks to the frame, but it was never clear to me if that spot on the frame was a smart/valid location to lift the RV at (...Can the frame BEND if jacked up in the wrong spot and do damage?? Anyone know?). On my 30' RVs, I could mount scissor jacks on the frame but it was about 3-4 feet behind the rear axle. Anyone know if that would be okay, or would it put too much stress on the frame?

Unfortunately, I could not find a good spot for scissor jacks on the front axle/area. Again it would need to be on the frame and about 3' behind the front axle. Anyone know if that would be a bad idea? Might be a moot point, as it didn't seem like there was enough clearance on the front to permanently mount scissor jacks.

Now that I'm thinking about it again, maybe it would be reasonable (at least for me) to mount some of these scissor jacks on just the rear (Pending input from others on frame bending...). I recently went camping at a rural campsite that was too sloped for my leveling blocks to get me level (I was off by probably 3-4 inches front to back). Having jacks could have helped. With them in just the rear, I could either back into a spot or pull into a spot depending on which way it was sloping and then the jacks in the rear would come in handy. Hmmm.....

OP: Please let us know if you mount 4 jacks on your class C and if so let's see some pictures. Maybe you will encourage me to give it another look.

Happy camping!
Chris

[CA_Traveler]

Not sure why you read that - Perhaps inadequate frame support? A scissor jack is a type of leveling jack. Why 45 deg? If 10K rating is adequate you'll need larger rating for 45 deg.